Operation Manual – IPv6 ManagementH3C S3100 Series Ethernet Switches Chapter 1 IPv6 Configuration1-71.1.3 Introduction to IPv6 Neighbor Discovery ProtocolThe IPv6 neighbor discovery protocol (NDP) uses five types of ICMPv6 messages toimplement the following functions:z Address resolutionz Neighbor unreachability detectionz Duplicate address detectionz Router/prefix discoveryz Address autoconfigurationz RedirectionTable 1-3 lists the types and functions of ICMPv6 messages used by the NDP.Table 1-3 Types and functions of ICMPv6 messagesICMPv6 message FunctionUsed to acquire the link-layer address of aneighborUsed to verify whether the neighbor is reachableNeighbor solicitation (NS)messageUsed to perform a duplicate address detectionUsed to respond to a neighbor solicitation messageNeighbor advertisement (NA)message When the link layer address changes, the localnode initiates a neighbor advertisement messageto notify neighbor nodes of the change.Router solicitation (RS)messageAfter started, a host sends a router solicitationmessage to request the router for an address prefixand other configuration information for the purposeof autoconfiguration.Used to respond to a router solicitation messageRouter advertisement (RA)messageWith the RA message suppression disabled, therouter regularly sends a router advertisementmessage containing information such as addressprefix and flag bits.Redirect messageWhen a certain condition is satisfied, the defaultgateway sends a redirect message to the sourcehost so that the host can reselect a correct next hoprouter to forward packets.
